The Ethiopian had been reading from Isaiah (53:7-8), a passage first heard by a weak nation in tribulation caused by a powerful invader, a passage about suffering.
Who is the Ethiopian talking about--himself or somebody else?
Philip responded by telling him about Jesus.
Christians continue to appropriate the stories of Israel in exile. Some of us think all the prophets were talking about Jesus. Some of us think that we can understand the meaning of Jesus better as we learn the history of God's dealing with suffering through the millennia that preceded Jesus' time on earth.